1. Field of the Invention
With reference to the classification of art as established in and by the United States Patent Office the present invention is believed to be found in the General Class entitled, "Surgery" (Class 128) and in the subclass therein entitled, "dosing devices--mixing syringes" (subclass 218 M).
2. Description of the Prior Art
The introduction of the hypodermic syringe and the like in which a movable plunger is used to draw fluid into the main barrel has been known for many years.
Intermixing syringes are, of course, not new and many attempts have been made to positively isolate powder from the diluent portion of the medicant during storage. Included in such proposed devices is U.S. Pat. No. 3,327,710 issued to FREEBERG on June 27, 1967. In this particular device the diluent is carried in one tube and the powder is carried in another tube. Means for puncturing of the barrier wall is provided to enable the diluent to be mixed with the powder.
Also of note is U.S. Pat. No. 3,534,734 to BUDRECK AS issued on Oct. 20, 1970; U.S. Pat. No. 3,489,147 to SHAW as issued on Jan. 13, 1970; U.S. Pat. No. 3,527,212 as issued to CLARK on Sept. 8, 1970; U.S. Pat. No. 3,303,846 as issued on Feb. 14, 1967; U.S. Pat. No. 3,542,023 as issued on Nov. 24, 1970 and U.S. Pat. No. 3,563,415 issued on Feb. 16, 1971, all three being issued to OGLE.
Also noted is U.S. Pat. No. 3,506,006 to LANGE as issued on Apr. 14, 1970; U.S. Pat. No. 3,405,712 issued to PIERICK on Oct. 15, 1968 and four patents to the Applicant, these being U.S. Pat. No. 3,464,412 as issued on Sept. 2, 1969; U.S. Pat. No. 3,566,859 as issued on Mar. 2, 1971; U.S. Pat. No. 3,659,749 as issued on May 2, 1972 and U.S. Pat. No. 3,678,930 as issued on July 25, 1972.
All of the above-noted patents are directed toward the intermixing of a powder and a diluent. However, these several devices, above-identified and others that are known, require a special syringe or a special container or both. The cost of establishing the necessary tooling and the associated production lines have deprived these devices of widespread acceptance. In the present invention the powder and the diluent are separately packaged. This powder is stored in a very thin glass ampule by common everyday techniques well known in the trade. The necessary sterilization procedures are also known and established. The plastic outer housing into which this ampule is contained and stored is commonly available and packaging of such an ampule in a sterile condition presents no problem.
The diluent is carried in a glass tube-like member which is slidable within an outer housing of plastic. This outer housing is conventional in shape and has a forward end with a hub provided for attachment of a hollow needle which is provided for injection. This device provides storage of the powder in a hermatically sealed glass ampule. The diluent is also enclosed in glass and is only moved into a mixing condition after the glass ampule has been broken. One-way valve means is provided to insure transfer and expelling of the mixed medicant. The mixed fluid is fed through a filter to remove any possible particles of glass or undissolved portions. An end insert secured in the front end of the outer housing provides a tapered projection by which the glass ampule is broken and has small passageways which exclude the larger glass portions before filtration.